The Pinning of Large Y2BaCuO5 Precipitates in YBa2Cu3O7-δ Films
K. Miyahara；H. Kawamura；T. Fujiyoshi；H. Kubota；R. Miyagawa
Chinese Journal of Physics
|Volume or Term/Year and Month of Publication||
34卷2S期（1996 / 04 / 01）
280 - 283
Y2BaCuO5 is a good substance as pinning centers. The magnetic field and temperature dependence of the pinning potential U(B,T) under the perpendicular field to c-axis was obtained as U(B,T) = U0(1-T/Tc)^3/2/B^1/2 in c-axis oriented YBa2Cu3O7-δ films with high density of YsBaCuO5 precipitates. A straightforward consideration leads to U(B,T) the symbol is abbreviated (Bc^2/2μ0)af^2el/af for a large pinning center, where af^2e is the effective pinning volume and l/af is the effective number of pinned flux lines per the cross section of precipitates which faces against the flux motion. The magnetic field and temperature dependence of the above expression is coincident with our experimental results.